organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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COMMUNICATIONS
ISSN: 2056-9890

3-Chloro-6-{4-[3-(4-chloro­phen­­oxy)prop­yl]piperazin-1-yl}pyridazine

aSchool of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China, and bBeijing Institute of Pharmacology and Toxicology, Beijing 100850, People's Republic of China
*Correspondence e-mail: xiaojunhai@139.com

(Received 3 February 2010; accepted 9 February 2010; online 27 February 2010)

In the title compound, C17H20Cl2N4O, the piperazine ring adopts a chair conformation and the dihedral angle between the pyridazine ring and the benzene ring is 36.3 (1)°. In the crystal, weak C—H⋯O and C—H⋯(N,N) inter­actions help to establish the packing, which also features short inter­molecular Cl⋯Cl contacts [3.331 (2) Å].

Related literature

For the biological properties of 3-(piperazin-1-yl)pyridazine derivatives, see: Monge et al. (1991[Monge, A., Aldana, I., Alvarez, T., Font, M., Santiago, E., Latre, J. A., Bermejillo, M. J. & Lopez-Unzu, M. J. (1991). J. Med. Chem. 34, 3023-3029.]); Tucker et al. (1998[Tucker, J. A., Allwine, D. A., Grega, K. C., Barbachyn, M. R., Klock, J. L., Adamski, J. L., Brickner, S. J., Hutchinson, D. K., Ford, C. W., Zurenko, G. E., Conradi, R. A., Burton, P. S. & Jensen, R. M. (1998). J. Med. Chem. 41, 3727-3725.]). For the synthesis, see: Fan et al. (2009[Fan, S. Y., Zheng, Z. B., Mi, C. L., Zhou, X. B., Yan, H., Gong, Z. H. & Li, S. (2009). Bioorg. Med. Chem. 17, 621-624.]).

[Scheme 1]

Experimental

Crystal data
  • C17H20Cl2N4O

  • Mr = 367.27

  • Monoclinic, C 2/c

  • a = 39.774 (18) Å

  • b = 5.757 (3) Å

  • c = 14.924 (7) Å

  • β = 93.107 (9)°

  • V = 3412 (3) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.39 mm−1

  • T = 113 K

  • 0.20 × 0.18 × 0.08 mm

Data collection
  • Rigaku Saturn CCD area-detector diffractometer

  • Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005[Rigaku/MSC (2005). CrystalClear. Rigaku/MSC, The Woodlands, USA.]) Tmin = 0.926, Tmax = 0.969

  • 11904 measured reflections

  • 2996 independent reflections

  • 2030 reflections with I > 2σ(I)

  • Rint = 0.061

Refinement
  • R[F2 > 2σ(F2)] = 0.050

  • wR(F2) = 0.159

  • S = 1.09

  • 2996 reflections

  • 217 parameters

  • H-atom parameters constrained

  • Δρmax = 0.30 e Å−3

  • Δρmin = −0.33 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C3—H3⋯N1i 0.95 2.53 3.247 (6) 133
C3—H3⋯N2i 0.95 2.50 3.427 (6) 164
C13—H13⋯O1ii 0.95 2.60 3.529 (5) 168
Symmetry codes: (i) x, y+1, z; (ii) [-x+{\script{3\over 2}}, -y-{\script{1\over 2}}, -z+1].

Data collection: CrystalClear (Rigaku/MSC, 2005[Rigaku/MSC (2005). CrystalClear. Rigaku/MSC, The Woodlands, USA.]); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

Pyridazine derivatives are important aromatic heterocycle compounds in the field of medicinal chemistry: for example, 3-(piperazin-1-yl)pyridazine derivatives are reported to possess anti-inotropic, anti-blood platelet aggregation (Monge et al., 1991), anti-bacterial (Tucker et al., 1998) and anti-viral activities (Fan et al., 2009).

The diagram of the title compound is shown in Fig.1. The bond lengths and angles are generally within normal ranges. The piperazine ring in the molecule adopts chair conformation. The dihedral angle between the pyridazine ring and the benzene ring is 36.3 (1)°.

In the crystal structure, the molecules are linked by intermolecular Cl2···Cl1 (symmetry code: x, 1+y, z), C7—H7A···Cl1 (symmetry code: -1/2+x, -1/2-y, 1/2+z) and N1···H3···N2 (symmetry code: 2-x, -y, 1-z) interactions (Fig. 2).

Related literature top

For the biological properties of 3-(piperazin-1-yl)pyridazine derivatives, see: Monge et al. (1991); Tucker et al. (1998). For the synthesis, see: Fan et al. (2009).

Experimental top

Diethyl azodicarboxylate (0.002 mol) was added in small portions to a stirred solution of 3-(4-(6-chloropyridazin-3-yl)piperazin-1-yl)pro-1-ol (0.002 mol), 4-chlorophenol (0.002 mol) and triphenylphosphine (0.002 mol) in anhydrous THF (10 ml). The mixture was stirred for 24 h at room temperature (Shi-Yong Fan et al., 2009). After removal of the THF under reduced pressure, the residue was purified by column chromatography (petroleum ether/acetone, 2:1, v/v) to afford the title compound as a colourless solid. Colourless prisms of (I) were prepared by slow evaporation of a solution of the title compound in ethanol at room temperature.

Refinement top

The C—H H atoms were placed in ideal positions and were refined using as riding model. With C—H=0.95 Å (aromatic), 0.99 Å (methylene) and Uiso(H)=1.2Ueq(C).

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2005); cell refinement: CrystalClear (Rigaku/MSC, 2005); data reduction: CrystalClear (Rigaku/MSC, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) with displacement ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. The crystal packing of (I) with Cl···Cl, C—H···N and C—H···O interactions shown as dashed lines.
3-Chloro-6-{4-[3-(4-chlorophenoxy)propyl]piperazin-1-yl}pyridazine top
Crystal data top
C17H20Cl2N4OF(000) = 1536
Mr = 367.27Dx = 1.430 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
a = 39.774 (18) ÅCell parameters from 5597 reflections
b = 5.757 (3) Åθ = 2.1–28.0°
c = 14.924 (7) ŵ = 0.39 mm1
β = 93.107 (9)°T = 113 K
V = 3412 (3) Å3Prism, colourless
Z = 80.20 × 0.18 × 0.08 mm
Data collection top
Rigaku Saturn CCD area-detector
diffractometer
2996 independent reflections
Radiation source: rotating anode2030 reflections with I > 2σ(I)
Multilayer monochromatorRint = 0.061
Detector resolution: 14.63 pixels mm-1θmax = 25.0°, θmin = 2.1°
ω and ϕ scansh = 4646
Absorption correction: multi-scan
(CrystalClear; Rigaku/MSC, 2005)
k = 66
Tmin = 0.926, Tmax = 0.969l = 1517
11904 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.050Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.159H-atom parameters constrained
S = 1.09 w = 1/[σ2(Fo2) + (0.0834P)2]
where P = (Fo2 + 2Fc2)/3
2996 reflections(Δ/σ)max = 0.003
217 parametersΔρmax = 0.30 e Å3
0 restraintsΔρmin = 0.33 e Å3
Crystal data top
C17H20Cl2N4OV = 3412 (3) Å3
Mr = 367.27Z = 8
Monoclinic, C2/cMo Kα radiation
a = 39.774 (18) ŵ = 0.39 mm1
b = 5.757 (3) ÅT = 113 K
c = 14.924 (7) Å0.20 × 0.18 × 0.08 mm
β = 93.107 (9)°
Data collection top
Rigaku Saturn CCD area-detector
diffractometer
2996 independent reflections
Absorption correction: multi-scan
(CrystalClear; Rigaku/MSC, 2005)
2030 reflections with I > 2σ(I)
Tmin = 0.926, Tmax = 0.969Rint = 0.061
11904 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0500 restraints
wR(F2) = 0.159H-atom parameters constrained
S = 1.09Δρmax = 0.30 e Å3
2996 reflectionsΔρmin = 0.33 e Å3
217 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl11.06826 (2)0.31802 (19)0.30198 (6)0.0238 (3)
Cl20.64299 (2)0.03379 (19)0.75503 (6)0.0252 (3)
O10.77076 (5)0.0299 (4)0.57543 (16)0.0172 (6)
N11.01144 (7)0.4149 (6)0.37004 (19)0.0191 (8)
N20.98066 (6)0.3697 (6)0.40118 (19)0.0177 (7)
N30.93922 (6)0.1129 (5)0.44101 (19)0.0159 (7)
N40.87083 (6)0.0635 (5)0.49145 (19)0.0149 (7)
C11.02999 (8)0.2401 (7)0.3457 (2)0.0177 (9)
C21.02128 (8)0.0067 (7)0.3520 (2)0.0182 (9)
H21.03600.11330.33490.022*
C30.99070 (8)0.0412 (7)0.3837 (2)0.0182 (8)
H30.98320.19670.38980.022*
C40.97035 (8)0.1495 (7)0.4072 (2)0.0154 (8)
C50.92000 (8)0.3152 (7)0.4675 (2)0.0180 (8)
H5A0.93530.43010.49750.022*
H5B0.90900.38920.41370.022*
C60.89344 (8)0.2413 (7)0.5311 (2)0.0179 (9)
H6A0.88000.37860.54710.021*
H6B0.90470.17970.58690.021*
C70.89091 (8)0.1374 (7)0.4665 (2)0.0156 (8)
H7A0.90210.20570.52120.019*
H7B0.87590.25690.43840.019*
C80.91722 (8)0.0697 (7)0.4018 (2)0.0164 (8)
H8A0.90600.01300.34510.020*
H8B0.93090.20740.38790.020*
C90.84595 (8)0.0032 (7)0.5562 (2)0.0169 (8)
H9A0.85790.04710.61280.020*
H9B0.83280.14380.56940.020*
C100.82186 (8)0.1877 (7)0.5241 (2)0.0169 (8)
H10A0.83460.33450.51930.020*
H10B0.81230.14780.46350.020*
C110.79342 (8)0.2255 (7)0.5855 (2)0.0158 (8)
H11A0.80240.23780.64850.019*
H11B0.78140.37130.56930.019*
C120.74176 (8)0.0403 (7)0.6207 (2)0.0146 (8)
C130.71859 (8)0.1366 (7)0.6022 (2)0.0171 (8)
H130.72360.25630.56120.020*
C140.68822 (8)0.1390 (7)0.6433 (2)0.0163 (8)
H140.67230.25870.63010.020*
C150.68135 (8)0.0346 (7)0.7035 (2)0.0169 (8)
C160.70436 (8)0.2093 (7)0.7240 (2)0.0181 (8)
H160.69950.32590.76640.022*
C170.73474 (8)0.2130 (7)0.6819 (2)0.0167 (8)
H170.75060.33310.69510.020*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0167 (5)0.0310 (7)0.0242 (5)0.0050 (4)0.0056 (4)0.0013 (4)
Cl20.0177 (5)0.0342 (7)0.0246 (5)0.0029 (4)0.0080 (4)0.0021 (4)
O10.0139 (12)0.0165 (16)0.0217 (14)0.0030 (11)0.0047 (10)0.0055 (12)
N10.0185 (15)0.018 (2)0.0211 (17)0.0044 (13)0.0046 (13)0.0023 (14)
N20.0160 (15)0.015 (2)0.0222 (17)0.0029 (13)0.0045 (12)0.0017 (14)
N30.0141 (14)0.0119 (19)0.0220 (17)0.0007 (12)0.0046 (12)0.0033 (13)
N40.0135 (14)0.0108 (19)0.0207 (16)0.0004 (12)0.0046 (12)0.0012 (13)
C10.0127 (16)0.024 (3)0.0170 (18)0.0020 (16)0.0017 (14)0.0004 (17)
C20.0168 (18)0.017 (3)0.021 (2)0.0021 (16)0.0000 (15)0.0007 (17)
C30.0179 (18)0.014 (2)0.022 (2)0.0014 (15)0.0007 (15)0.0009 (17)
C40.0165 (17)0.013 (2)0.0164 (19)0.0002 (15)0.0012 (14)0.0008 (16)
C50.0167 (17)0.012 (2)0.026 (2)0.0007 (16)0.0029 (15)0.0022 (17)
C60.0166 (17)0.013 (2)0.024 (2)0.0004 (15)0.0030 (14)0.0042 (16)
C70.0166 (17)0.011 (2)0.020 (2)0.0008 (15)0.0024 (14)0.0008 (16)
C80.0179 (17)0.015 (2)0.0172 (19)0.0014 (15)0.0034 (14)0.0037 (16)
C90.0165 (17)0.017 (2)0.0170 (19)0.0013 (16)0.0017 (14)0.0026 (16)
C100.0167 (17)0.015 (2)0.0197 (19)0.0008 (15)0.0038 (14)0.0008 (16)
C110.0158 (17)0.012 (2)0.0197 (19)0.0019 (15)0.0014 (14)0.0010 (16)
C120.0130 (17)0.016 (2)0.0153 (18)0.0018 (15)0.0008 (13)0.0033 (16)
C130.0194 (18)0.014 (2)0.0174 (19)0.0016 (16)0.0000 (14)0.0024 (16)
C140.0176 (17)0.015 (2)0.0166 (19)0.0045 (15)0.0015 (14)0.0020 (16)
C150.0134 (17)0.021 (2)0.0166 (19)0.0017 (16)0.0036 (14)0.0041 (16)
C160.0205 (18)0.017 (2)0.0164 (19)0.0034 (16)0.0002 (14)0.0034 (16)
C170.0157 (17)0.018 (2)0.0164 (19)0.0034 (15)0.0006 (14)0.0004 (16)
Geometric parameters (Å, º) top
Cl1—C11.747 (3)C7—C81.513 (4)
Cl2—C151.745 (3)C7—H7A0.9900
O1—C121.369 (4)C7—H7B0.9900
O1—C111.445 (4)C8—H8A0.9900
N1—C11.311 (5)C8—H8B0.9900
N1—N21.358 (4)C9—C101.518 (5)
N2—C41.337 (5)C9—H9A0.9900
N3—C41.378 (4)C9—H9B0.9900
N3—C51.459 (5)C10—C111.509 (5)
N3—C81.469 (4)C10—H10A0.9900
N4—C91.462 (4)C10—H10B0.9900
N4—C71.465 (4)C11—H11A0.9900
N4—C61.466 (4)C11—H11B0.9900
C1—C21.392 (5)C12—C171.389 (5)
C2—C31.357 (5)C12—C131.391 (5)
C2—H20.9500C13—C141.383 (5)
C3—C41.419 (5)C13—H130.9500
C3—H30.9500C14—C151.382 (5)
C5—C61.518 (5)C14—H140.9500
C5—H5A0.9900C15—C161.383 (5)
C5—H5B0.9900C16—C171.392 (5)
C6—H6A0.9900C16—H160.9500
C6—H6B0.9900C17—H170.9500
C12—O1—C11116.9 (3)C7—C8—H8A109.6
C1—N1—N2118.6 (3)N3—C8—H8B109.6
C4—N2—N1119.4 (3)C7—C8—H8B109.6
C4—N3—C5118.2 (3)H8A—C8—H8B108.1
C4—N3—C8119.4 (3)N4—C9—C10113.7 (3)
C5—N3—C8111.7 (3)N4—C9—H9A108.8
C9—N4—C7112.2 (3)C10—C9—H9A108.8
C9—N4—C6108.8 (3)N4—C9—H9B108.8
C7—N4—C6108.8 (3)C10—C9—H9B108.8
N1—C1—C2125.2 (3)H9A—C9—H9B107.7
N1—C1—Cl1114.9 (3)C11—C10—C9113.2 (3)
C2—C1—Cl1119.9 (3)C11—C10—H10A108.9
C3—C2—C1116.8 (3)C9—C10—H10A108.9
C3—C2—H2121.6C11—C10—H10B108.9
C1—C2—H2121.6C9—C10—H10B108.9
C2—C3—C4117.6 (4)H10A—C10—H10B107.7
C2—C3—H3121.2O1—C11—C10108.0 (3)
C4—C3—H3121.2O1—C11—H11A110.1
N2—C4—N3117.0 (3)C10—C11—H11A110.1
N2—C4—C3122.4 (3)O1—C11—H11B110.1
N3—C4—C3120.5 (3)C10—C11—H11B110.1
N3—C5—C6109.8 (3)H11A—C11—H11B108.4
N3—C5—H5A109.7O1—C12—C17124.1 (3)
C6—C5—H5A109.7O1—C12—C13115.9 (3)
N3—C5—H5B109.7C17—C12—C13120.0 (3)
C6—C5—H5B109.7C14—C13—C12120.3 (3)
H5A—C5—H5B108.2C14—C13—H13119.8
N4—C6—C5112.1 (3)C12—C13—H13119.8
N4—C6—H6A109.2C15—C14—C13119.3 (3)
C5—C6—H6A109.2C15—C14—H14120.4
N4—C6—H6B109.2C13—C14—H14120.4
C5—C6—H6B109.2C14—C15—C16121.2 (3)
H6A—C6—H6B107.9C14—C15—Cl2119.6 (3)
N4—C7—C8111.3 (3)C16—C15—Cl2119.3 (3)
N4—C7—H7A109.4C15—C16—C17119.5 (4)
C8—C7—H7A109.4C15—C16—H16120.3
N4—C7—H7B109.4C17—C16—H16120.3
C8—C7—H7B109.4C12—C17—C16119.8 (3)
H7A—C7—H7B108.0C12—C17—H17120.1
N3—C8—C7110.4 (3)C16—C17—H17120.1
N3—C8—H8A109.6
C1—N1—N2—C40.9 (5)C4—N3—C8—C7160.2 (3)
N2—N1—C1—C22.5 (5)C5—N3—C8—C756.0 (4)
N2—N1—C1—Cl1177.3 (2)N4—C7—C8—N357.3 (4)
N1—C1—C2—C31.9 (5)C7—N4—C9—C1057.1 (4)
Cl1—C1—C2—C3177.8 (2)C6—N4—C9—C10177.6 (3)
C1—C2—C3—C40.2 (5)N4—C9—C10—C11172.0 (3)
N1—N2—C4—N3178.7 (3)C12—O1—C11—C10175.1 (3)
N1—N2—C4—C31.1 (5)C9—C10—C11—O171.7 (4)
C5—N3—C4—N20.0 (5)C11—O1—C12—C177.1 (5)
C8—N3—C4—N2141.5 (3)C11—O1—C12—C13173.0 (3)
C5—N3—C4—C3177.5 (3)O1—C12—C13—C14178.8 (3)
C8—N3—C4—C341.0 (5)C17—C12—C13—C141.3 (5)
C2—C3—C4—N21.6 (5)C12—C13—C14—C150.8 (5)
C2—C3—C4—N3179.1 (3)C13—C14—C15—C160.5 (5)
C4—N3—C5—C6160.3 (3)C13—C14—C15—Cl2179.6 (3)
C8—N3—C5—C655.4 (4)C14—C15—C16—C171.2 (5)
C9—N4—C6—C5179.6 (3)Cl2—C15—C16—C17178.9 (3)
C7—N4—C6—C557.9 (4)O1—C12—C17—C16179.5 (3)
N3—C5—C6—N457.0 (4)C13—C12—C17—C160.6 (5)
C9—N4—C7—C8178.2 (3)C15—C16—C17—C120.6 (5)
C6—N4—C7—C857.7 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3···N1i0.952.533.247 (6)133
C3—H3···N2i0.952.503.427 (6)164
C13—H13···O1ii0.952.603.529 (5)168
Symmetry codes: (i) x, y+1, z; (ii) x+3/2, y1/2, z+1.

Experimental details

Crystal data
Chemical formulaC17H20Cl2N4O
Mr367.27
Crystal system, space groupMonoclinic, C2/c
Temperature (K)113
a, b, c (Å)39.774 (18), 5.757 (3), 14.924 (7)
β (°) 93.107 (9)
V3)3412 (3)
Z8
Radiation typeMo Kα
µ (mm1)0.39
Crystal size (mm)0.20 × 0.18 × 0.08
Data collection
DiffractometerRigaku Saturn CCD area-detector
diffractometer
Absorption correctionMulti-scan
(CrystalClear; Rigaku/MSC, 2005)
Tmin, Tmax0.926, 0.969
No. of measured, independent and
observed [I > 2σ(I)] reflections
11904, 2996, 2030
Rint0.061
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.050, 0.159, 1.09
No. of reflections2996
No. of parameters217
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.30, 0.33

Computer programs: CrystalClear (Rigaku/MSC, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3···N1i0.952.533.247 (6)133
C3—H3···N2i0.952.503.427 (6)164
C13—H13···O1ii0.952.603.529 (5)168
Symmetry codes: (i) x, y+1, z; (ii) x+3/2, y1/2, z+1.
 

Acknowledgements

The work was supported by National Natural Science Foundation of China (90813025).

References

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